Birds in flight basics – Focusing

In this second part of our look at photographing birds in flight we are concentrating on focusing, writes Andrew James. Without doubt focusing is an area that causes a lot of confusion with photographers – especially relative newcomers to it – but even seasoned photographers get in a muddle sometimes. I’m going to talk in generic ‘best practice’ terms rather than look at any specific extra settings that some high-end cameras may have.

To start with, if you are shooting a moving subject you must have your autofocus mode set to Continuous-AF or AI Servo as Canon calls it. Depending on your camera make there will be variations in the name but ‘Continuous-AF’ is the most used term.

With Continuous AF (I’ll just call it AF-C from now on) enabled your camera/lens combo will do its best to try to keep the focus on whatever moving subject the active AF points are positioned on.

I use the words “do its best to try to keep focus” deliberately because AF-C is not a panacea for getting sharp shots of moving subjects. Why? Well there are a lot of factors at work that mean that AF-C is far from perfect. What are they?

1 You’re the problem!
It’s not easy following a moving subject through a long lens so your aim may well shift off the thing you want to focus on. The camera can’t do the following for you – that’s down to you – as is selecting the right AF points to have active and positioning them in the right place on your subject. We’ll come back to this later.

2 Lack of contrast
The amount of contrast on the subject is also important. The active AF points need contrast in order to lock onto your subject. Sadly, nature hasn’t made every bird’s feathers have contrast at the right point on their body. This means often other things in the scene may have lots more contrast and naturally that’s where the lens really wants to focus if you let it! Plus of course, you have the tricky issue of light conditions. Contrast is always improved in good light but we don’t only shoot in perfect conditions in the real world.

3 Camera and lens issues
Your equipment. Yep, not all cameras and lenses are born equal. Some have better and faster focusing abilities than others. Let’s be honest, even if you are Lewis Hamilton you won’t win a Formula 1 World Championship driving a Citroen 2CV. Not everyone wants to spend a small fortune on a camera or a lens. It doesn’t mean you can’t take birds-in-flight shots it just means you need to be aware of what your camera’s limitations are.

Photograph taken by Rosie Jackson

This is me in France photographing flamingo. Believe it or not I am actually photographing birds in flight using my trusty 300mm f/2.8. The low position is because I am photographing over a flock over flamingos to capture birds landing. The point of showing it is that whatever position you need to get yourself in you have to work hard to make the long lens as stable as possible. My position looks and was a bit of an effort but if you notice I have the camera and lens carefully held so there is no wobble from me.

Here is the resulting image. The exposure for this shot is 1/1600sec at f/5.6 and ISO 800.

The good news here is, if you practice your tracking, panning and holding techniques and use AF-C, then you ARE going to improve your chances of getting a bird-in-flight shot sharp, so only work in AF-C. But you do have to be realistic and not expect every shot to be perfectly sharp.

If you are a total newcomer to using AF-C rather than the camera’s default AF-mode of One-shot (Canon) or AF-S (Nikon), in order for the AF system to actually attempt to focus, you must half-depress the shutter button and keep it half-depressed while tracking your subject. The truth is, even doing this using AF-C, focus will often drop in and out for all those reasons just mentioned in 1 to 3 and possibly a few others I haven’t thought of!

However, let’s leave this section of this article with the simple fact that you MUST use AF-C when shooting birds-in-flight.

Drive Modes

Next, make sure your camera’s Drive mode is also set to Continuous shooting. In others words, you can take multiple shots one after the other as long as you keep your finger pressed right down on the shutter button. The camera’s default will be a single shot mode. This is too slow for action.

In this department, again not all cameras are equal. Some have a faster frame rate than others, but at least by setting Continuous you are giving yourself the best chance of nailing that perfect shot. In addition to the ‘haves’ and ‘have nots’ some cameras also have different speed ratings for continuous shooting. If yours does, then stick it on the fastest setting unless you can think of a valid reason to slow it down.

I’m not advocating that you then simply ‘machine-gun’ all your shots. Shoot in short bursts (three or four frames) when the bird is large enough in the frame, and the continuous rapid-fire sequence of shots will help you to get that one perfect image.

Continuous focus and high speed drive mode is essential.

Active Autofocus points

Now we can actually get to the Active AF points themselves. To the uninitiated, these are the square things you can see overlaid when you look through the viewfinder. Guess what? Yep, not all cameras are equal. Some give you more AF points than others and you are able to select different groupings of them. Typically, the higher up the camera scale you go, the more points you will get and the more groupings you get. For example, my Canon EOS 1DX-Mk II has 61 AF Points and I can select seven different ‘groupings’ of them, from single-point AF for absolute precision focusing to the whole lot of them. That’s a lot of decision-making!

 

You know what, even the AF points aren’t equal! I’m not going to go into the techie ins and outs, but effectively, some can be more sensitive than others. As a typical rule of thumb, your most sensitive AF points will be at the centre and around the centre. Here’s my advice to try to keep this simple:

* If you are photographing a bird against a plain sky with little or no distractions, use a large group.

* If you are photographing a bird against a busier background such as trees, use a smaller group.

* If you are a smart arse, use a really small group or even just a single point!

These decisions come with some caveats.

A large group of active AF points means you have a much greater chance of accidentally focusing on something in the background or the wrong place on the bird itself. This is why I’m suggesting you only do it when the background is sky or something very distant and indistinct. To get around the focusing on any part of the bird then use a smaller aperture such as f/8 for greater depth-of-field and therefore get some leeway with sharpness.

The smaller group of active AF points (as below) means you have to be much more accurate with your tracking of the bird. To be honest, this is the one I favour, as accuracy should always be your goal.

A small group of central focus points has been set.

Being a smart arse and using one AF point is good but it will let you down sometimes. I find being a smart arse is best when the birds are less erratic in their motion, larger in size or when they are landing, as they are slowing down at this point. If you can, do it, accuracy is always to be strived for.

Just one AF point for this puffin but it was putting the brakes on!

In all cases, I’d suggest you keep your active AF points central – at least until you’ve become a bird-in flight ninja and then feel free to move them around for compositional reasons. Otherwise, stick central, leave a little bit of extra room around the subject and then crop for composition. Don’t crop 50%, but 10 to 25% is okay. For example, like the two shot below.

If you are reading this and your camera only gives you limited options, such as either one active AF point or all of them, then the decision is made for you. Personally I’d start by using them all, regardless of the background and then progress to trying to be more accurate.

The other thing to remember is when you actually engage focus on the bird itself. If you are able to track it for some distance, don’t try to lock focus too early. Pick it up when it’s about 50% of where you want it to be in the frame and then follow it, using AF-C and your central group of AF points. Remember to half depress the shutter button so the AF-C is continually trying to keep focus.

One point that’s worth noting here is that a bird flying at speed directly towards you is much harder for the camera to focus on and keep in focus. This is because there’s less obvious signs of motion for the AF system to make sense of, whereas a bird flying at angle across the area in front of you is much easier to pick up on and keep in focus.

Birds-in-flight skills summary

1 Use a fast shutter speed if you want a sharp shot. 1/1000sec and faster if possible

2 Be calm and accurate with your panning and tracking

3 Use AF-C (AI Servo in Canon-speak)

4 Set Continuous shooting on the Drive mode and half depress the shutter button to try to keep focus on your subject

5 Don’t focus on it when the subject is too distant or you will struggle to keep that focus throughout its flight

6 Fire your shots in short bursts at the optimum time – this is when you think the subject is almost large enough in the frame

Use a small central group of active AF points unless shooting a bird against a plain sky where a larger group is okay

8 Keep those AF groups central for the most accurate focusing

9  Use a single AF point or the smallest group possible if you are a smart arse

10 Remember not all cameras and lenses are equal, so if you are struggling don’t beat yourself up too much. The more you practise, the better you will get, no matter what kit you are using

Oh and finally – keep your fingers crossed!

Published in Camera Skills
2 Comments
  1. Some cameras, I use a Sony A6500, will happily latch on to a subject remembering it even if it moves out of the viewfinder temporarily. This is all very well, but you still need to think about backgrounds, aperture and shutter speed (crisply focussed with motion blur is no great advantage unless that’s what you are aiming for). I tend to use a wider lens setting rather than come in tightly on the bird and crop afterwards.

  2. Thanks AJ, a good reminder. I keep my camera on single point focus and forget to change it for BIFs – then kick myself when they are out of focus. Duh…..

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